[OpenSIPS-Users] [NEW] Dialog end-points pinging

[Vlad Paiu]

Hello,

OpenSIPS trunk has recently been enhanced and now allows the dialog 
end-points to be pinged via SIP OPTIONS messages.
This feature can help detecting ghost calls, being an alternative to the 
RTP timeout notification, when the server does not handle the media in 
any way.

The create_dialog() function [1], provided by the dialog module,also 
receives a string parameter, which specifies whether the dialog 
end-points should be pinged via SIP options messages. The parameter can 
be "P" to specify to only ping the caller, "p" to only ping the callee 
or "Pp" to ping both dialog sides.

If the extra string parameter is provided at dialog creation and one 
end-point fails to respond to a options ping ( 408 Timeout ), or if the 
response is a 481 ( Call/Transaction Does Not Exist ) OpenSIPS will 
terminate the dialog from the middle.
The interval between two SIP pings can be configured via a dialog module 
parameter [2].

[1] http://www.opensips.org/html/docs/modules/devel/dialog.html#id293972
[2] http://www.opensips.org/html/docs/modules/devel/dialog.html#id292965

Regards,

-- 
Vlad Paiu
OpenSIPS Developer